| Today I did an engine and transmission oil change on the 300SE. I don’t normally post basic maintenance to this website as it really isn’t that interesting. In this case, I used to tips I learned form MercedesSource videos that really sped up the job. MercedesSource are an online parts vendor, who also make some useful special tools. The owner, Kent, runs a youtube channel to promote the business. I’ve bought a couple of his special tools over the years and found them quite useful. The first tip was for removing the bolt from the transmission oil pan. This […] A common feature of Mercedes cars from the mid 70s through the mid 2000s is the self-leveling rear suspension. This system is standard on the wagons, but was commonly specified on the higher end sedans too. Mercedes-Benz Australia was particularly keen on the system fitting it to coupes and even mid size saloons. The system ensures that even with a heavy load in the rear of the car, the suspension remains level. Keeping the car level improves handling and safety. It is actually quite a simple system, derived from the more complex system on the 6.9. This system, in turn […] A few months ago I replaced the under bonnet insulation pad on my 560SEC. This job also needed doing on the 300SE. I purchased both pads at the same time, and finally got a chance to do the second one today. Note, if you’re looking for more information on forums, American sites will refer to this as a hood pad. There are youtube videos by Kent Bergsma and Pierre Hedary on Hood Pad replacement. For the 560SEC, I had a genuine Mercedes part. The coupe is different to the sedan. For the 300SE, I have one made by Febi. Unlike […] At least in Australia, by far the best month of the year to buy tyres is June. Both the tyre retailers and manufacturers offer attractive end of financial year sales. Most people don’t realize, but tread wear is not the only reason to replace tyres. As the rubber ages, it hardens. Once the tyres harden the handling, particularly in the wet is compromised. When I first purchased by 250SE I nearly spun it in the rain on an innocuous corner. The tread in the tyres looked fine, and I had thought no more of it. But on closer inspection they […] Back in early 2017 I fixed my broken odometer. The 300SE odometer repair was successful, but there were two things I needed to follow up on. The odometer was reading 10% low. I could hear the gears, especially in cold weather. In addition, some time after I repaired the odometer, one of the bulbs that illuminates the instrument cluster at night failed. The fix for all these things required the removal of the instrument cluster. The procedure to remove the cluster and the speedometer is covered in my previous article. The low reading was attributed to having the wrong gear. […] The motor mounts were changed on the 300SE around six months ago, but there was not time to do the Transmission mount. It was obvious it would need doing from the condition of the motor mounts. In addition, I was feeling some vibration from the drivetrain at various times. changing the W126 transmission mount is generally a simple affair. The transmission is jacked up a little, with care taken not to dent the pan. The mount is freed via three bolts – two on the crossmember with a 13mm socket and one to the tail of the transmission with a […] The saga of my non functional A/C is now over. The 300SE is blowing cold air. It would want to after all the parts I had to change to get this far. The final piece of the puzzle was the Klima relay. This relay controls the engagement of the compressor and had burned out when the clutch shorted. I ended up buying a rebuilt relay from the same vendor as my rebuilt Climate Control Unit. The A/C is fixed just in time for the hot Sydney summers. Coincidently, at the same time I needed to change the Klima relay, […] My fight with the W126 Air Conditioning system is almost over. When I purchased the car, the A/C worked rather well. After the water pump gave out, it looks like it shorted out the compressor clutch. Changing out the clutch is not much different to changing out the whole compressor, so I sourced a new compressor and receiver/drier. This was rather irritating as working air conditioning was factored into the price I paid for the car. I went through the entire climate control system of the car as part of my troubleshooting. I found that the car had a missing […] My story of fixing the W126 climate control can be summed up by: If everything points to a problem with an expensive part, don’t waste your time trying to replace the cheaper parts around it in a futile hope it will solve the problem! After trying a used Climate Control Unit, new fan resistor etc, I finally bit the bullet and bought a rebuilt climate control unit. This solved the problem. In retrospect I probably didn’t need to buy the resistor and I certainly didn’t need the used CCU. It also pays to shop around as a rebuilt CCU was […] I’ve been fighting with the W126 Climate Control system for the last few months – and it’s been winning. When I purchased the car in November last year, it was a very hot day and the A/C worked great. It had a new radiator, so I took the evidence of leaking coolant to be history rather than a current problem. Turned out the water pump was leaking and over the next 3 months that leak got worse. My theory is that the leaking coolant shorted out the compressor clutch, as it stopped working around the same time. I was able […] | |
